> [...] hydrogen doesn't really have any real downsides compared to batteries but has plenty of upsides. How about inefficiency? Conversion from electricity to

> [...] hydrogen doesn't really have any real downsides compared to batteries but has plenty of upsides. How about inefficiency? Conversion from electricity to hydrogen and back will get you only about 35% of the original energy. When using a hydrogen combustion engine instead of a fuel cell, comparison gets a little trickier, but at least the hydrogen generation will cost you about 35%.